Automated Test Plan Validation for Object Measurement by a Coordinate Measuring Machine

Abstract

A computer device includes memory that stores a test plan for a coordinate measuring machine to perform an object measurement. The test plan includes at least one test feature for a plurality of reference elements of the object. The computer device includes at least one processor configured to execute instructions stored in the memory. The instructions include, for each of the reference elements, obtaining at least one accuracy variable. The accuracy variable specifies an accuracy of the measurement result of a respective reference element. The instructions include ascertaining an error effect of each reference element on the quantification of the test feature based on the respective accuracy variable. The instructions include ascertaining for each of the error effects whether it meets an error criterion and, if so, classifying a reference element assigned to this error effect as a critical reference element.

1 . (canceled) 
     
     
         2 . A computer-implemented method comprising:
 obtaining a test plan for measurement of an object with a coordinate measuring machine that includes a measurement sensor, wherein:
 the test plan includes a test feature to be quantified within a scope of the measurement, and 
 a quantification of the test feature is implemented based on a set of measurement results of a set of reference elements of the object by the coordinate measuring machine; 
   for each reference element of the set of reference elements, obtaining an accuracy variable that specifies an accuracy of the measurement result of the reference element;   ascertaining an error effect of each reference element of the set of reference elements on the quantification of the test feature based on the respective accuracy variable;   at least one of:
 ascertaining whether each of the error effects meets an error-free criterion and in response to one of the error effects meeting the error-free criterion:
 classifying the reference element assigned to this error effect as a noncritical reference element; and 
 automatically adapting the test plan to measure the noncritical reference element by adjusting at least one parameter that governs the measurement of the object by the coordinate measuring machine during execution of the test plan to obtain a faster measurement speed; and 
 
 ascertaining whether each of the error effects meets an error criterion and in response to one of the error effects meeting the error criterion:
 classifying the reference element assigned to this error effect as a critical reference element; and 
 at least one of:
 automatically adapting the test plan to measure the critical reference element by adjusting at least one parameter that governs the measurement of the object by the coordinate measuring machine during execution of the test plan to obtain a higher measurement accuracy; and 
 ascertaining, proposing, and/or implementing a set of countermeasures, wherein the set of countermeasures includes an adaptation of the measurement of the critical reference element, a new definition of the test feature, and/or a new selection of the reference element to be measured in response to the error criterion being satisfied; and 
 
 
   controlling the coordinate measuring machine to measure the object according to at least one of an adapted test plan and the set of countermeasures by moving at least one of the measurement sensor and the object to measure at least one of the noncritical reference element and the critical reference element.   
     
     
         3 . The method of  claim 2  wherein:
 the set of measurement results of the set of reference elements is ascertained based on a measurement result of a further reference element; and 
 an error effect on an achievable accuracy of the quantification is also ascertained for the further reference element. 
 
     
     
         4 . The method of  claim 2  wherein each reference element of the set of reference elements is a geometric element of the object. 
     
     
         5 . The method of  claim 2  wherein the measurement result of a reference element is ascertained in each case based on at least one coordinate value of the reference element. 
     
     
         6 . The method of  claim 5  wherein the coordinate value is ascertained based on at least one of a real object measurement and a simulated object measurement. 
     
     
         7 . The method of  claim 2  wherein the measurement result of a reference element in each case specifies at least one of a spatial degree of freedom and a dimension of the reference element. 
     
     
         8 . The method of  claim 2  wherein the accuracy variable is ascertained based on a statistical characteristic of a distribution of coordinate values that were determined to ascertain the measurement result of a respective reference element. 
     
     
         9 . The method of  claim 2  wherein the accuracy variable is ascertained based on a deviation of at least one coordinate value from a measurement result that was calculated from a plurality of coordinate values for a respective reference element. 
     
     
         10 . The method of  claim 2  wherein the accuracy variable is ascertained based on an adjustment method that is carried out to calculate the measurement result from a multiplicity of coordinate values. 
     
     
         11 . The method of  claim 2  wherein the accuracy variable is ascertained based on a form deviation of a respective reference element. 
     
     
         12 . The method of  claim 2  wherein the accuracy variable is ascertained based on an inherent measurement uncertainty of the coordinate measuring machine. 
     
     
         13 . The method of  claim 2  wherein:
 the error effect of a respective reference element is determined based on a possible value spectrum of the measurement result of a respective reference element; and 
 the value spectrum is determined based on the accuracy variable. 
 
     
     
         14 . The method of  claim 13  further comprising, based on the value spectrum of a respective reference element, ascertaining a possible quantification value spectrum of the test feature and comparing to an admissible tolerance range of a respective test feature. 
     
     
         15 . The method of  claim 14  wherein the error criterion is satisfied when the quantification value spectrum exceeds an admissible portion of the tolerance range of a respective test feature. 
     
     
         16 . The method of  claim 2  further comprising:
 ascertaining whether the error effect of a respective reference element satisfies an error criterion; and 
 in response to the error effect satisfying the error criterion, classifying a corresponding reference element as a critical reference element. 
 
     
     
         17 . The method of  claim 2  wherein the set of countermeasures are ascertained, proposed, and/or implemented automatically. 
     
     
         18 . A machine comprising:
 memory storing a test plan for measurement of an object with a coordinate measuring machine, wherein:
 the coordinate measuring machine includes a measurement sensor, 
 the test plan includes a test feature to be quantified within a scope of the measurement, and 
 a quantification of the test feature is implemented based on a set of measurement results of a set of reference elements of the object by the coordinate measuring machine; and 
   at least one processor configured to execute instructions stored in the memory, wherein the instructions include:
 for each reference element of the set of reference elements, obtaining an accuracy variable that specifies an accuracy of the measurement result of the reference element; 
 ascertaining an error effect of each reference element of the set of reference elements on the quantification of the test feature based on the respective accuracy variable; 
 at least one of:
 ascertaining whether each of the error effects meets an error-free criterion and in response to one of the error effects meeting the error-free criterion:
 classifying the reference element assigned to this error effect as a noncritical reference element; and 
 automatically adapting the test plan to measure the noncritical reference element by adjusting at least one parameter that governs the measurement of the object by the coordinate measuring machine during execution of the test plan to obtain a faster measurement speed; and 
 
 ascertaining whether each of the error effects meets an error criterion and in response to one of the error effects meeting the error criterion:
 classifying the reference element assigned to this error effect as a critical reference element; and 
 at least one of: 
  automatically adapting the test plan to measure the critical reference element by adjusting at least one parameter that governs the measurement of the object by the coordinate measuring machine during execution of the test plan to obtain a higher measurement accuracy; and 
  ascertaining, proposing, and/or 
 
 
   implementing a set of countermeasures, wherein the set of countermeasures includes an adaptation of the measurement of the critical reference element, a new definition of the test feature, and/or a new selection of the reference element to be measured in response to the error criterion being satisfied; and
 controlling the coordinate measuring machine to measure the object according to at least one of an adapted test plan and the set of countermeasures by moving at least one of the measurement sensor and the object to measure at least one of the noncritical reference element and the critical reference element. 
   
     
     
         19 . A non-transitory computer-readable medium comprising processor-executable instructions that include:
 obtaining a test plan for measurement of an object with a coordinate measuring machine that includes a measurement sensor, wherein:
 the test plan includes a test feature to be quantified within a scope of the measurement, and 
 a quantification of the test feature is implemented based on a set of measurement results of a set of reference elements of the object by the coordinate measuring machine; 
   for each reference element of the set of reference elements, obtaining an accuracy variable that specifies an accuracy of the measurement result of the reference element;   ascertaining an error effect of each reference element of the set of reference elements on the quantification of the test feature based on the respective accuracy variable;   at least one of:
 ascertaining whether each of the error effects meets an error-free criterion and in response to one of the error effects meeting the error-free criterion:
 classifying the reference element assigned to this error effect as a noncritical reference element; and 
 automatically adapting the test plan to measure the noncritical reference element by adjusting at least one parameter that governs the measurement of the object by the coordinate measuring machine during execution of the test plan to obtain a faster measurement speed; and 
 
 ascertaining whether each of the error effects meets an error criterion and in response to one of the error effects meeting the error criterion:
 classifying the reference element assigned to this error effect as a critical reference element; and 
 at least one of:
 automatically adapting the test plan to measure the critical reference element by adjusting at least one parameter that governs the measurement of the object by the coordinate measuring machine during execution of the test plan to obtain a higher measurement accuracy; and 
 ascertaining, proposing, and/or implementing a set of countermeasures, wherein the set of countermeasures includes an adaptation of the measurement of the critical reference element, a new definition of the test feature, and/or a new selection of the reference element to be measured in response to the error criterion being satisfied; and 
 
 
   controlling the coordinate measuring machine to measure the object according to at least one of an adapted test plan and the set of countermeasures by moving at least one of the measurement sensor and the object to measure at least one of the noncritical reference element and the critical reference element.